<VV> Fuel pump priming by hand

[Tony Underwood]

At 09:12 PM 5/29/2011, Frank DuVal wrote:
>Several of us in the central Virginia area have done this for years to
>prime the system after an extended shutdown, or replacement of fuel line
>parts.
>
>But a word of caution. We feel you can damage the diaphragms, especially
>older pumps, because you will typically be pushing the rod more than the
>.140" the engine pushes the rod.  If you try this method, be careful to
>limit travel.
>
>YMMV




I've always done this.   Never had a problem.   All it takes is 
common sense.   (I know, it's not common)


Good rule of thumb is to use a thumb.  Don't mash down any harder 
than you can, using just your thumb.   You should be OK.  Do NOT use 
the heel of your hand.

Remember that it is the SPRING inside the pump cover that actually 
pumps fuel under pressure.  The eccentric does NOTHING except raise 
the diaphragm up enough to compress that spring about 1/4" which 
sucks fuel into the pump...  and then lets it decompress and push 
fuel into the carbs.


No heel of hand, no anxious hard mashing, think about it.



tony..